SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a06518a5f28b32ac42f1f830b8139e4707bfb92758eb4a5d2c3fba984cbc12db' 
  AND token = 'H4sKiPYsKhvz7Kfjl4GF8GEgDywFYrGMVyg1/iMpOr4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}